ShareX - ShareX is a free and open source program that lets you capture or record any area of your screen...
X Steps Recorder - A clone of Microsoft's Problem Steps Recorder, but for linux.
ScreenToGif - This tool allows you to record a selected area of your screen and save as a animated gif.
Folge - The fastest tool for creating step-by-step guides.
recordit.co - Make a short video capture of your desktop as a gif.
Snagit - Screen Capture Software for Windows and Mac